Search Publications

The survey of planetary nebulae in Andromeda (M 31). III. Constraints from deep planetary nebula luminosity functions on the origin of the inner halo substructures in M 31
DOI: 10.1051/0004-6361/202038366 Bibcode: 2021A&A...647A.130B

Caldwell, Nelson; Freeman, Kenneth C.; Gerhard, Ortwin +4 more

Context. The Andromeda (M 31) galaxy displays several substructures in its inner halo. Different simulations associate their origin with either a single relatively massive merger, or with a larger number of distinct, less massive accretions.
Aims: The origin of these substructures as remnants of accreted satellites or perturbations of the pre…

2021 Astronomy and Astrophysics
eHST 34
Convective blueshift strengths of 810 F to M solar-type stars
DOI: 10.1051/0004-6361/202039607 Bibcode: 2021A&A...654A.168L

Reiners, A.; Zechmeister, M.; Jeffers, S. V. +1 more

Context. The detection of Earth-mass exoplanets in the habitable zone around solar-mass stars using the radial velocity technique requires extremely high precision, on the order of 10 cm s−1. This puts the required noise floor below the intrinsic variability of even relatively inactive stars, such as the Sun. One such variable is convec…

2021 Astronomy and Astrophysics
Gaia 34
Revisiting the archetypical wind accretor Vela X-1 in depth. Case study of a well-known X-ray binary and the limits of our knowledge
DOI: 10.1051/0004-6361/202040272 Bibcode: 2021A&A...652A..95K

Degenaar, N.; Utrilla, E.; Ramos-Lerate, M. +9 more

Context. The Vela X-1 system is one of the best-studied X-ray binaries because it was detected early, has persistent X-ray emission, and a rich phenomenology at many wavelengths. The system is frequently quoted as the archetype of wind-accreting high-mass X-ray binaries, and its parameters are referred to as typical examples. Specific values for t…

2021 Astronomy and Astrophysics
Exosat Gaia INTEGRAL 34
Multi-instrumental view of magnetic fields and activity of ɛ Eridani with SPIRou, NARVAL, and TESS
DOI: 10.1051/0004-6361/202040027 Bibcode: 2021A&A...648A..55P

Donati, J. -F.; Petit, P.; Vidotto, A. A. +6 more


Aims: We report on observations of the active K2 dwarf ɛ Eridani based on contemporaneous SPIRou, NARVAL and TESS data obtained over two months in late 2018, when the activity of the star was reported to be in a non-cyclic phase.
Methods: Near-infrared (NIR) spectropolarimetry was obtained using SPIRou over four nights in late September,…

2021 Astronomy and Astrophysics
Gaia 33
One star, two star, red star, blue star: an updated planetary nebula central star distance catalogue from Gaia EDR3
DOI: 10.1051/0004-6361/202142008 Bibcode: 2021A&A...656A.110C

Walton, N. A.; Chornay, N.

Context. Planetary nebulae (PNe) are a brief but important phase of stellar evolution. The study of Galactic PNe has historically been hampered by uncertain distances, but the parallaxes of PN central stars (CSPNe) measured by Gaia are improving the situation.
Aims: Gaia's Early Data Release 3 (EDR3) offers higher astrometric precision and gr…

2021 Astronomy and Astrophysics
Gaia eHST 33
X-ray flux in SED modelling: An application of X-CIGALE in the XMM-XXL field
DOI: 10.1051/0004-6361/202039401 Bibcode: 2021A&A...646A..29M

Ciesla, L.; Buat, V.; Boquien, M. +3 more

X-CIGALE is built on the spectral energy distribution (SED) code of CIGALE and implements important new features: the code accounts for obscuring material in the poles of AGNs and has the ability to fit X-ray fluxes. In this work, we used ∼2500 spectroscopic X-ray AGNs from the XMM-XXL-north field and examined the improvements the new features bri…

2021 Astronomy and Astrophysics
Herschel 33
AGN feeding and feedback in Fornax A. Kinematical analysis of the multi-phase ISM
DOI: 10.1051/0004-6361/202141143 Bibcode: 2021A&A...656A..45M

Gaspari, M.; Serra, P.; Smirnov, O. +10 more

We present a multi-wavelength study of the gaseous medium surrounding the nearby active galactic nucleus (AGN), Fornax A. Using MeerKAT, ALMA, and MUSE observations, we reveal a complex distribution of the atomic (H I), molecular (CO), and ionised gas in its centre and along the radio jets. By studying the multi-scale kinematics of the multi-phase…

2021 Astronomy and Astrophysics
eHST 32
Stereoscopy of extreme UV quiet Sun brightenings observed by Solar Orbiter/EUI
DOI: 10.1051/0004-6361/202141010 Bibcode: 2021A&A...656A..35Z

Barczynski, K.; Haberreiter, M.; Mierla, M. +27 more

Context. The three-dimensional fine structure of the solar atmosphere is still not fully understood as most of the available observations are taken from a single vantage point.
Aims: The goal of the paper is to study the three-dimensional distribution of the small-scale brightening events ("campfires") discovered in the extreme-UV quiet Sun b…

2021 Astronomy and Astrophysics
SolarOrbiter 32
The GAPS Programme at TNG. XXVIII. A pair of hot-Neptunes orbiting the young star TOI-942
DOI: 10.1051/0004-6361/202039042 Bibcode: 2021A&A...645A..71C

Baratella, M.; Mallonn, M.; Scandariato, G. +48 more

Context. Young stars and multi-planet systems are two types of primary objects that allow us to study, understand, and constrain planetary formation and evolution theories.
Aims: We validate the physical nature of two Neptune-sized planets transiting TOI-942 (TYC 5909-319-1), a previously unacknowledged young star (50-20+30

2021 Astronomy and Astrophysics
Gaia Hipparcos 32
TOI-1201 b: A mini-Neptune transiting a bright and moderately young M dwarf
DOI: 10.1051/0004-6361/202141587 Bibcode: 2021A&A...656A.124K

Amado, P. J.; Caballero, J. A.; Pallé, E. +63 more

We present the discovery of a transiting mini-Neptune around TOI-1201, a relatively bright and moderately young early M dwarf (J ≈ 9.5 mag, ~600-800 Myr) in an equal-mass ~8 arcsecond-wide binary system, using data from the Transiting Exoplanet Survey Satellite, along with follow-up transit observations. With an orbital period of 2.49 d, TOI-1201 …

2021 Astronomy and Astrophysics
Gaia 32